WASHINGTON — Republican John McCain has nearly erased Democrat Barack Obama’s national lead and turned the presidential contest into a dead heat, according to the latest NBC News/Wall Street Journal poll.

In that poll, Obama holds a narrow one-point lead over McCain (47-46 percent), which is down from his three-point advantage in August (45-42 percent) and six-point edge in July (47-41 percent).

The findings from this survey — which was conducted of 860 registered voters from Sept. 6-8, and which has a margin of error of plus-minus 3.3 percentage points — are consistent with other recent national polls showing the race to essentially be tied after the conventions and vice presidential selections.

Looking inside the numbers, McCain’s pick of Sarah Palin as his running mate appears to have not only attracted female voters, but boosted McCain’s association with changing the country’s direction, and energized members of the Republican Party.

Excited RepublicansIn fact, the number of GOP respondents who say they're excited about McCain’s candidacy is nearly three times higher than it was last month.

The poll also shows that Obama has improved his standing on some key issues, including several publically-perceived shortcomings. They include whether he would be a risky choice for president and whether he shares certain voters' values and backgrounds.

It's more evidence that this presidential contest keeps getting tighter.

“This is kind of the political equivalent of the tortoise and the hare,” said Republican pollster Neil Newhouse, who conducted this survey with Democrat Peter D. Hart. “McCain continues to gain as we get closer to Election Day.”

“The Palin factor is remarkable,” said Newhouse. “She has clearly added an excitement factor. There is no question about that.”

Indeed, 34 percent of McCain voters say they’re excited about his candidacy, which is up from 12 percent in August.

But Republicans still face a significant enthusiasm gap in their contest with Democrats. The percentage of Obama voters who say they’re excited about his candidacy is now at 55, up nine points from last month.

Overall, 34 percent say the Palin selection makes them more likely to vote for McCain, versus 25 percent who say the opposite. Forty percent believe it doesn’t make a difference.

By comparison, 24 percent say that Obama’s selection of Joe Biden to be his running mate makes them more likely to vote for the Illinois Democrat in the fall, compared to 16 percent who say the pick makes them less likely to vote for him.

“Clearly, Sarah Palin has hit a gusher,” said Hart. “All of these things say that her initial introduction to American has been a very solid and positive introduction.”

But Hart cautioned that her boost could be fleeting.

He recalled a similar bounce after Walter Mondale unveiled Geraldine Ferraro as his running mate in 1984. “The faster they rise, the steeper they descend.”

“He hasn’t shaken the perception that his programs and policies would be closely aligned with President Bush’s,” explained Newhouse, the GOP pollster.

McCain, however, has made some progress in portraying himself as an agent of change.

According to the poll, 35 percent say that the Arizona senator is very likely or somewhat likely to bring real change to the country. That’s up considerably from June, when just 21 percent said that about McCain.

By comparison, 52 percent believe that Obama would bring change to the country, which is up four points since June.

Indeed, if it weren’t for the bounce that McCain appears to have received after the Palin pick, the attention would be on much of the progress Obama has made in this poll.

His favorability-unfavorability rating stands at 53-32 percent, which is up from 50-36 percent in August; 53 percent say they identify with Obama’s values and background, up three points since August and six points since July; and 48 percent believe that Obama would be the riskier choice for president, which is down three points from last month.

“This is a person who is doing exactly what he needs to do to put himself in a position to win this election,” Hart says.